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arXiv · 2206.13548

A VLA View of the Flared, Asymmetric Disk Around the Class 0 Protostar L1527 IRS

Patrick D. Sheehan·John J. Tobin·Zhi-Yun Li·Merel L. R. van 't Hoff·Jes K. Jørgensen·Woojin Kwon·Leslie W. Looney·Nagayoshi Ohashi·Shigehisa Takakuwa·Jonathan P. Williams·Yusuke Aso·Sacha Gavino·Itziar de Gregorio-Monsalvo·Ilseung Han·Chang Won Lee·Adele Plunkett·Rajeeb Sharma·Yuri Aikawa·Shih-Ping Lai·Jeong-Eun Lee·Zhe-Yu Daniel Lin·Kazuya Saigo·Kengo Tomida·Hsi-Wei Yen
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Abstract

We present high resolution Karl G. Jansky Very Large Array (VLA) observations of the protostar L1527 IRS at 7 mm, 1.3 cm, and 2 cm wavelengths. We detect the edge-on dust disk at all three wavelengths and find that it is asymmetric, with the southern side of the disk brighter than the northern side. We confirm this asymmetry through analytic modeling and also find that the disk is flared at 7 mm. We test the data against models including gap features in the intensity profile, and though we cannot rule such models out, they do not provide a statistically significant improvement in the quality of fit to the data. From these fits, we can however place constraints on allowed properties of any gaps that could be present in the true, underlying intensity profile. The physical nature of the asymmetry is difficult to associate with physical features due to the edge-on nature of the disk, but could be related to spiral arms or asymmetries seen in other imaging of more face-on disks.

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Patrick D. Sheehan, John J. Tobin, Zhi-Yun Li, Merel L. R. van 't Hoff, Jes K. Jørgensen, Woojin Kwon, Leslie W. Looney, Nagayoshi Ohashi, Shigehisa Takakuwa, Jonathan P. Williams, Yusuke Aso, Sacha Gavino, Itziar de Gregorio-Monsalvo, Ilseung Han, Chang Won Lee, Adele Plunkett, Rajeeb Sharma, Yuri Aikawa, Shih-Ping Lai, Jeong-Eun Lee, Zhe-Yu Daniel Lin, Kazuya Saigo, Kengo Tomida, Hsi-Wei Yen. 2022-06-27. A VLA View of the Flared, Asymmetric Disk Around the Class 0 Protostar L1527 IRS. https://doi.org/10.3847/1538-4357%2Fac7a3b

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